I used this scenario quite a lot just to test out what was new etc. Given what happened historically, if you can force a draw with the Protestants that is pretty good. You'd need your opponent to make a big mistake to do much better. Its much the same in reverse.
To me this plays like a short scenario between two relatively well matched forces and it tends to stalemate as a result. You don't really have the time or map area to do much to break that situation.
The Bohemian scenario is a bit more dynamic - more targets, a bit of a switch in force balance and the scope for movement.
Supply really is key in TYW. So look for where they have supply sources and see if you can disrupt that - even if you can't capture a depot you might be able to take military control over the province and/or loot it (ie reduce its supply value). This is like some of the older Wars in America scenarios - starvation becomes a military tool and I have come to really prioritise defending my few large supply bases or trying to disrupt those of my opponent.
AJE The Hero, The Traitor and The Barbarian
PoN Manufacturing Italy; A clear bright sun
RoP The Mightiest Empires Fall
WIA Burning down the Houses; Wars in America; The Tea Wars